# std::is_member_function_pointer

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< cpp‎ | types

Defined in header `<type_traits>` |  |
template< class T > struct is_member_function_pointer; |  | (since C++11)

`std::is_member_function_pointer` is a UnaryTypeTrait.

Checks whether `T` is a non-static member function pointer. Provides the member constant `value` which is equal to true, if `T` is a non-static member function pointer type. Otherwise, `value` is equal to false.

If the program adds specializations for `std::is_member_function_pointer` or `std::is_member_function_pointer_v`, the behavior is undefined.

### Template parameters

T | - | a type to check

### Helper variable template

template< class T > constexpr bool is_member_function_pointer_v = is_member_function_pointer<T>::value; |  | (since C++17)

## Inherited from std::integral_constant

### Member constants

value [static] | true if `T` is a member function pointer type, false otherwise (public static member constant)

### Member functions

operator bool | converts the object to bool, returns value (public member function)
operator() (C++14) | returns value (public member function)

### Member types

Type | Definition
`value_type` | bool
`type` | std::integral_constant<bool, value>

### Possible implementation

    template<class T>
    struct is_member_function_pointer_helper : std::false_type {};

    template<class T, class U>
    struct is_member_function_pointer_helper<T U::*> : std::is_function<T> {};

    template<class T>
    struct is_member_function_pointer
        : is_member_function_pointer_helper<typename std::remove_cv<T>::type> {};

### Example

Run this code

    #include <type_traits>

    class A
    {
    public:
        void member() {}
    };

    int main()
    {
        // fails at compile time if A::member is a data member and not a function
        static_assert(std::is_member_function_pointer<decltype(&A::member)>::value,
                      "A::member is not a member function.");
    }

### See also

is_pointer (C++11) | checks if a type is a pointer type (class template)
is_member_object_pointer (C++11) | checks if a type is a non-static member object pointer (class template)
is_member_pointer (C++11) | checks if a type is a pointer to a non-static member function or object (class template)

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